dtmf timing, sub-khz frequency resolution

examples/DTMF/DTMF.ino

@@ -47,6 +47,7 @@ void setup() {
   
   // let the AU ot of reset
   digitalWrite(RESET_PIN, HIGH);
+  delay(5); // wait for device to come up
   
   Serial.println("beginning radio setup");
 
@@ -73,6 +74,8 @@ void setup() {
   Serial.println("changing frequency");
   freq = 420000;
   radio.frequency(freq);
+  Serial.print("new frequency: ");
+  Serial.println(radio.getFrequency());
   
   // set RX volume to minimum to reduce false positives on DTMF rx
   radio.setVolume1(6);
@@ -88,6 +91,16 @@ void setup() {
 
   // set up DTMF
   radio.enableDTMFReceive();
+  
+  /* DTMF timing settings are optional.
+   * These times are set to default values when the device is started.
+   * You may want to change them if you're DTMF receiver isn't detecting
+   * codes from the HamShield (or vice versa).
+   */
+  radio.setDTMFDetectTime(24); // time to detect a DTMF code, units are 2.5ms
+  radio.setDTMFIdleTime(50); // time between transmitted DTMF codes, units are 2.5ms
+  radio.setDTMFTxTime(60); // duration of transmitted DTMF codes, units are 2.5ms
+  
   Serial.println("ready");
 }
 
@@ -145,7 +158,6 @@ void loop() {
         dtmf_to_tx = false;
       }
     }
-    delay(20); // make sure the last code is done
     // done with tone
     radio.setModeReceive();
     radio.setTxSourceMic();
@@ -185,4 +197,4 @@ char code2char(uint16_t code) {
   }
  
   return c;
-}
+}

src/HamShield.h

@@ -240,7 +240,9 @@ class HamShield {
         void safeMode();
 		
 		bool frequency(uint32_t freq_khz);
+        bool frequency(float freq_khz);
 		uint32_t getFrequency();
+		float getFrequency_float();
 			
 		// channel mode
 		// 11 - 25kHz channel
@@ -392,6 +394,12 @@ class HamShield {
         //   Writing a single DTMF code:
         //     setDTMFCode(code); // code is a uint16_t from 0x0 to 0xF
 		void enableDTMFReceive();
+		void setDTMFDetectTime(uint16_t detect_time);
+        uint16_t getDTMFDetectTime();
+        void setDTMFIdleTime(uint16_t idle_time); // idle time is time between DTMF Tone
+        uint16_t getDTMFIdleTime();
+        void setDTMFTxTime(uint16_t tx_time); // tx time is duration of DTMF Tone
+        uint16_t getDTMFTxTime();
 		uint16_t disableDTMF();
 		uint16_t getDTMFSample();
 		uint16_t getDTMFCode();
@@ -480,7 +488,7 @@ class HamShield {
         uint16_t radio_i2c_buf[4];
 		bool tx_active;
 		bool rx_active;
-        uint32_t radio_frequency;
+        float radio_frequency;
 /*        uint32_t FRS[];
         uint32_t GMRS[];
         uint32_t MURS[];